Imaging an Aquifer for a Groundwater Supply Wellfield

2025 NGWA Groundwater Week

Aestus highlighted how electrical resistivity imaging can save significant costs on your water supply project at NGWA’s Groundwater Week in 2025

Groundwater scientists and professional well drillers know, in some regions, not every well is a winner. What if you could increase your odds of drilling high-yield water wells?

Aestus’ CEO, Stuart McDonald, presented a technical poster at the 2025 NGWA Groundwater Week on the benefits of using Aestus’ specialty electrical resistivity imaging technology on groundwater projects. For Aestus’ client in Oklahoma, scanning before drilling meant saving time, decreasing total project cost, and improving client satisfaction.

The city of Guymon was looking for a place to build a groundwater well field in the semi-arid, High Plains region of Oklahoma. In this area, groundwater wells are ideally drilled into the channelized, coarse-grained intervals of the Ogallala Aquifer. However, these channels are sometimes difficult to target, since they can vary both vertically and laterally over short distances. Additionally, the lowering water table in the region presents challenges to drilling a successful water well. Guymon’s consultant team decided to bring Aestus onto the project to pinpoint well drilling locations.

Aestus collected ERI data in a large grid of ~1 square mile to depths of ~700 feet below ground surface. The electrical data were then integrated into a 3D model with regional hydrogeology information. The electrical “scans” identified electrically resistive zones of significant thicknesses, as shown by blue zones on the ERI cross sections (see below). These zones were interpreted to be coarse-grained channels of the Ogallala Aquifer.

Seven test wells were targeted by Aestus’ client based on interpretation of the electrical images. All seven test wells were deemed to be a success, with each well estimated to produce upwards of 1 million gallons per day (MGD).

Due to the project’s success, an estimated $7.8M saved by stakeholders. Costs were saved by reducing the number of test wells drilled to reach project objectives and overall time spent on the project (see below graphic for more information).

The discussion at NGWA reinforced a broader industry trend: groundwater professionals are increasingly seeking non-intrusive tools to make better decisions.

Aestus - Optimizing Wellfield Development Poster FINAL

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    Samantha Frandsen
    Since joining Aestus in 2018, Samantha has performed all aspects of the Aestus project lifecycle, including acquisition field work, processing of geophysical data, data integration, 3D visualization, and reporting. As project manager, she oversees a variety of projects completed at complex sites across the United States and strives to help our clients efficiently leverage Aestus’ high-resolution GeoTrax Survey™ data to improve understanding of subsurface conditions. When she’s not investigating what’s below the ground, Samantha enjoys exploring all the above-ground fun her Stateline (South Lake Tahoe), NV home has to offer via trail running, mountain biking, and snowboarding. Samantha is based out of Stateline, Nevada.

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    Madison Culver
    Madison Culver, M.Sc.
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